(a) Field of the Invention
The present invention relates to novel .gamma.-lactonecarboxylic acid derivatives (2-substituted-5-oxo-2-tetrahydrofurancarboxylic acid derivatives) which are useful as antibacterial agents or intermediates for synthesizing the same, and to a process for preparing the derivatives.
(b) Description of the Prior Art
Recently, a novel antibiotic, TAN-588 (hereinafter sometimes referred to briefly as "TAN-588"), exhibiting antibacterial activity on gram-positive bacteria and gram-negative bacteria was discovered from new strains belonging to the genus Empedobacter and the genus Lysobacter isolated from soil (see Unexamined EPC Publication No. 0157544). Subsequently, it has been found that TAN-588 has a unique chemical structure represented by 2-[(4S)-4-acetamido-3-oxo-2 -isoxazolidinyl]-5-oxo-2-tetrahydrofurancarboxylic acid.
The invention searches for novel TAN-588 derivatives having outstanding antibacterial activity and provides intermediates which are useful for preparing the derivatives.
We have conducted research on the synthesis of TAN-588 derivatives and found that novel 2-substituted-5oxo-2-tetrahydrofurancarboxylic acid derivatives include those having antibacterial activity and that these compounds can be useful intermediates for preparing TAN-588 derivatives. We have carried out further research and accomplished the present invention.